Revert "Remove dead branch"

This reverts commit e2e5ca2.

Author: Your Name

externals/simplecpp/simplecpp.cpp

@@ -2332,6 +2332,9 @@ namespace simplecpp {
             const Token *nextTok = B->next;
 
             if (canBeConcatenatedStringOrChar) {
+                if (unexpectedA)
+                    throw invalidHashHash::unexpectedToken(tok->location, name(), A);
+
                 // It seems clearer to handle this case separately even though the code is similar-ish, but we don't want to merge here.
                 // TODO The question is whether the ## or varargs may still apply, and how to provoke?
                 if (expandArg(tokensB, B, parametertokens)) {